First lady Michelle Obama spoke for many Americans when she referred to the Cleveland kidnapping case as "a parent's worst nightmare." The fact that the three female victims were found a decade after they disappeared is truly reason for celebration and hope. But three key areas deserve more attention to try to prevent such kidnappings from happening in the future.

Missing children: First, we need to put the Cleveland case in perspective. Up to 800,000 children go missing every year. Most are runaways or have been kidnapped by a parent during a child custody battle. In these cases, the child's life is usually not in danger.

The Cleveland case is as rare as it is horrendous. But numbers aren't everything. We have to treat missing teenage and preteenage girls in a different manner from other missing children. Most long-term abductions and homicides involve sexual assaults of attractive girls who are 11 and older. This was the case with Elizabeth Smart, who was 14 when she was taken from her home for nine months. Jaycee Dugard was only 11 and was held by a recidivist sex offender for 18 years.

For missing teenage and preteenage girls, we need a much faster response — not 24 hours, not six hours, not even two hours. Most youngsters abducted for sexual purposes are dead or imprisoned within a couple of hours.

Parents should immediately get in touch with police. Police should immediately treat the missing child as an abducted victim. Amber Alerts should be announced within minutes, not hours.

Granted, this approach would be costly. We would make lots of mistakes. But we would also save lives and prevent long-term confinements.

Predators in our midst: In Cleveland, accused kidnapper Ariel Castro apparently had never been convicted of any sexual offenses. But he seemed to have possessed common characteristics of sexual predators. He apparently had no trouble abusing his captives and was accused multiple times of domestic violence, which left his spouse with severe physical injuries.

He had a need for control, where he is accused of restraining his victims with ropes and chains. He had the sociopathic charm, where neighbors and friends regarded him as the good brother who was polite and charming.

Not every predator is caught, arrested, convicted and sentenced to lengthy prison terms. But we can still do a better job of keeping track of those sex offenders who have been caught. Most abductions in which children are sexually assaulted are perpetrated by men who have a history of committing sexual offenses.

Dugard was found in 2009 when two police officers became suspicious after seeing Phillip Garrido with his two daughters. When Garrido's background was checked, they discovered he was a registered sex offender.

Police response to cold cases: Traditionally, after months, the police might continue to keep an eye on the circumstances of a child who is still missing. But they also move on to investigate intensively more current cases — crimes that have a higher likelihood of a positive resolution and continue to be featured prominently in the mass media.

The absence of adequate police resources and the presence of immense public pressure to solve the "crime of the week" combine to minimize the attention paid to "cold cases." It becomes all too easy to assume that the kidnapping victim has been murdered because that is the statistical reality. Formally, kidnapping cases remain open for at least a year, but typically they fade from police scrutiny.

Yearly, only about 100 abducted children are murdered or kept in captivity for long periods of time. The numbers might be small, but the pain and suffering are enormous.

In either case, even a single kidnapping that results in freedom for its victims gives hope to the families of abducted children everywhere that their loved ones, too, could someday be coming home.

Jack Levin is the Brudnick Professor of Sociology and Criminology at Northeastern University and co-author of Extreme Killing.

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